Såheim is the third plant in the Rjukan string, and was built in 1914.

The magnificent power plant building was designed by architect Thorvald Astrup and Professor Olaf Nordhagen, and has the nickname the Såheim Opera. Såheim, together with the Vemork power plant, laid the foundation for the entire industrial development in Rjukan. Såheim has been expanded several times, and currently produces electricity using a water drop of 273 meters from the Vemork plant and three Francis turbines.